Orchidaceae

Habenaria siamensis Schltr.

Son La Province, Thuan Chau District, forest near Chieng Pac Commune, terrestrial orchid in limestone area, leaves 2, opposite, spreading close to the ground, flower sepals pale green-white, petals very pale green-white, lip white, flowers arrange on the top of inflorescence (not laxly spreading like H. tonkinensis), sidelobes of lip clearly longer than mid lobe, filiform slenderer than mid lobe, spur clavate, as long as pedicel with ovary, pedicel and ovary minutely papillose, sepals outside surface and margin minute densely papillose. 12 August 2023, Truong Ba Vuong, BV 1819 (VNM 00060083).